schedule:
- New _execution_loop runs alongside _database_event_loop. It claims
job.node.execute rows, sets a 30-min lease on available_at, then
dispatches each as asyncio.create_task under a Semaphore(N).
Polling loop is back to sub-millisecond turnaround for
schedule.run.requested and job.node.finished. Long notebook
execution no longer blocks DAG advance events.
- _process_pending_events filters by event_type IN
('schedule.run.requested', 'job.node.finished'); the executor
loop owns job.node.execute exclusively.
- _process_outbox_event builds a plain dict envelope before
handler dispatch; the previous ORM-row handoff risked
DetachedInstanceError once the outer session closed.
- _sync_once uses get_job + reschedule_job for existing job ids
instead of add_job(replace_existing=True). Each cron schedule
no longer removed-and-readded every 5s.
- service.py threads settings.schedule_execution_concurrency into
the orchestrator (default 4).
common:
- create_async_engine gets explicit pool_size=10, max_overflow=20,
pool_recycle=1800. No more relying on SQLAlchemy defaults.
- New schedule_execution_concurrency setting.
runtime:
- scan_workspaces: add missing 'import os' (NameError on startup)
and switch to asyncio.gather bounded by Semaphore(4) so N
workspaces start in parallel instead of sequentially.
Co-Authored-By: Claude <noreply@anthropic.com>
Replace uvicorn with gunicorn + UvicornWorker in backend, runtime,
and schedule Dockerfiles. New gunicorn.conf.py per service exposes
bind/workers/timeout/graceful_timeout as GUNICORN_* env knobs.
Notable details:
- schedule: timeout=0 (disables gunicorn worker heartbeat) so long
notebook execution isn't killed by gunicorn's silent-worker kill.
- All three configs: drop dead threads=4 setting; UvicornWorker is
async and ignores threads.
- Pin gunicorn>=26.0.0 in each pyproject; uv.lock regenerated.
- Drop stale 'COPY contracts ./contracts' from runtime and schedule
Dockerfiles (contracts dir was deleted in an earlier refactor;
builds would have failed).
- backend Dockerfile: switch to uv sync layout matching runtime/
schedule; add build deps for native wheels.
Co-Authored-By: Claude <noreply@anthropic.com>
tao.chen